Improvement in balance piston-valves and gears



Z SheetsS'heet 1.

Patenigd March 7,1876.

WITNESSES Attorney.

ZSheets-SheetZ.

J. WHITNEY. BALANCE PISTON VALVE AND GEAR. No.174.-,6 0Z. Patented March 7,1876.

1,; I l. d 6

WITNESSES IJV'VEJV'TOR 6 .Att orney.

" JAMESI-W -I ii- Y; K TI t i AK?) TA at r o a Y.

Specification forming pa r'tof Letters PatentNo. l;74l,602,'"dated Marc-h 7, 1 87li;-application filed Toalltbhomit maycon'cernt Yankton,.in .the"county of 'Y'an'kton. and Ten.

ritory of Dakota, have invented certain'new' and useful improvements in 'Balance."'Piston-. Valves; and. I do herebydeclare the follow ing tof'be ,a full, clear, 'and'fexact description of the invention, such asw'ill enable othersskilled inthe art to which i'tpertains to-make' and useit, reference beingh'a'd to theaccompanying drawings, which form -part of this fi at o I My invention relates to certain improvements in piston-valves andvalve-gearand'it; consists in certain-details" of construction and combinations of parts, which will more; fully appear from the following'descriptioii and claims.

Figure 1 represents a plan view of the valve-chest and valve-gear. Fig. 2 shows the piston valve detached from its chest. Fig. 3

shows a portion of the"valve-chest. Fig. 4 is a longitudinal section of the piston, showing the combination of the packing-ringstherewith. Fig. 5 represents one of the packingrings.

A is the valve-chest, formed of the upper and lower half-sections, around which are formed the annular steam-passages b. The heads B B of the valve-chest are provided with openings or boxes 0 c for the passage of the ends of valve-stem C. The balance-valve D consists of four pistons, d, the space between said pistons being cut away to form concave recesses e, as shown in the drawings; or the several pistons may be formed complete in themselves, and keyed to the valve-stem. As

at present constructed the balance-valve D is made up of the detachable sections 1, 2, 3, 4, 5, 6, and 7, between each of which sections metallic packing-rings are secured. These sections may be made of any desired length to insure any desired lap or lead to the valve. The packing-rings on one side are cut partly through, as at 9, while the opposite side of the ring is formed with an overlapping joint, h, which construction effectually prevents the escape of steam, not only through the packing-rings in a longitudinal direction, but also in a vertical direction. The balance-valve D may be secured to the valve-stem by a key or nut',"as desiredilTh einterior ofthe'valve- Be it 'knownftha't' I',*JAM'ES WHITNEY, of

chest, oppositejeach of the-steam-passages b,

isprovidedwith twoor morerows of perforations, f, preferably circular inform, and'said perforations are, arranged in suoh a'inanner that"anfo 'iening in one rowshal'l 'be' between -t-woopenings of the opposite-"rowof perforations,i1'i orderthat :the wear on'thepiston ,shall be equalized. The central "enlarged portion of'the valve D has steam-passages t leadingfrom thejoutside of the-valve in an inclined direction to the inner periphery of the central packing-rings Theinner surface of r the packin'g rings is-equal to the aggregate area 'of perforations f, so thatas the valve moves over the steam-port'F livesteam, which flows from the Stfifllihitllfilf G. and surrounds the central portionfand balances the'valve, "will'pass through the perforations-f, leading port F through openings 'i'inthe valve, and enter beneath and exert sufficient pressure on the interior of the packing-rings to equalize the pressure on the entire outer surface of the rings as they are passing over the steam-ports.

Were it not for the construction above set forth the pressure of steam on the outer surface of the packing-rings would contract the rings to such an extent that live steam would flow by the same into the exhaust-passage of the valve-chest.

The central packing-rings H are formed with passages j, leading to the inner surface of the ring. tion to exhaust, steam will flow through passages j, and exert suflicient pressure on the interior of the ring to counterbalance the pressure on the outer surface of the same. Exhaust steam may escape from the exhaust-ports I When the valve moves in a direc-' gins er the ens. This ishaftfihasaasplineg'k,

which engages with a groove, l, formediina sliding variable cam-shaft, R, which may either be made solid or in sections, as desired. K is a yoke, attached to the valve-stem, the

outer endnof: said yoke, having-arod orbxw- 'j sliding in a guide, or bearing to steadyand support the-"same while in operation; The cam is constructed to snugly. fiti'theyoke to. impart a smooth and steady stroke to the valve. The-sliding cam-shaft as shown, is formed vin such a manner thatbfy, simply; vary:- ing its position on shaft I steam may cut. off at any desired stroke of the piston, or the shaft may be thrown completely out ofengagea ment, with the; yoke,.inj. order; to entirely out.

off steam from the cylinder, and allow z the. V val ve to remain stationary, in its, ohestwhenja: locomotive -isrunning down-ggrade I with. in :;m y. improved yahv-e,-,muohaltime, lalior,

" amtex'pense will beeeonomigeditherehyn Y The beariugsin, the lie-"1411i: 0ft the valves;

chest 2, serving was; guides,vv fee the. valve-stem,

-- and-also to'support the.weightiofzfthe val the headset the.ivalvesehesti are not wily ground to make a. steam joint f pressurqwas in ordinary,- valves. Erov-ision is;

- made for the esoape ofi any steamafrow'the;

ends nofwthe, valve-chest; should? any; escape; thereto. v The; endsrofi. the cylinder; are RIO? videdl. with small perforations-i;o toe which. pi es leadin g. to. the; exhaustmipepom s n k arch-are-secured:v

Hav-in g fully; describedi lnyyihyeution ,1, what? I claim, and desireto; secureiby. wtlfltP-at'r" ent, i

1. The valve-chest ,havihga; the) --external ports,; the steam. and exhaustiports of each :row'bein gr separated by ai central inertitiornand the-cylinder prouided withirows;

. of: perforations .leadingtoeachexternal;port,

all: constructed and. arranged; substantially as v and for the purpose specified I v a simple andhghtmeaus of attachmentxmaybe; used, asthey: are not .obliged toiresistz. steam;

I having passages j, with lthetvalve ,D. and per forated cylinder, substantially as. and for the purpose specified, r

the samesconstrlicted'z. with variable 1 cam-sun faeeg, as shown whereby variable, intermit- .fQpln edtwith'i variable cam-surfaces, substantially as andgforzth'e purpose specified; j J

. .8.-v Thecombnation, withthe yokeK, of'the sliding eam-shaftalt, .ithe' latter.v having a; partions of] its length; or; 'less; iMK BfBI':' tH3-IJ the opening of the, yoke, whereby the cam-shaft may be thrown;completelyout of engagement with :the -,yoke, ,ifi'desired, substantially. as and have; hereu'nto aset; my hand, this .24th;day o'f semua w smp Q v JAMESWHITNEY.

WitnessesE" V I M I .THOS.,B.IHALL,-..

51; The combinationof the packing-rings H,

, 6.35m combinatiomwith theyoke,K,seeu 'red. tothewvalve-stem, iof,l the vsliding.earnesha'ftiR,

teutimovements -may be impartedto-the' valve, 'suhst'ant'iall ylas andj for% the purpose set forth. a 7 .t Thepcomhiuatiomwith the; rotary shaftl; provided; with. spline. It, of? the; sliding] camshaftR, having-aigroove, l, thesaid cam-shaft 

